The present invention relates to transceiver modules. More specifically, the invention relates to transceiver modules with electrically looped back signals that can emulate faults of optical transceiver modules.
Currently, optical network devices are present in most all high speed networks. The industry is continually improving on the bandwidth and features of these network devices. One of the largest expenses in releasing new optical devices relates to testing the devices during the many different stages of development, such as software verification testing, hardware verification testing and manufacturing testing.
FIG. 1 shows many conventional ways of testing optical network devices. An optical network device (or system) 1 can include one or more linecards 3. The line cards are typically inserted into connectors and are connected electrically through a backbone to other hardware (and software) within optical network device 1.
Optical transceivers 5 are connected to linecards 3 and convert optical signals to electrical signals, and vice versa. Many conventional optical transceivers conform to the “small form-factor pluggable” (SFP) standard. SFP transceivers are designed to be high bandwidth, small physical size and easily changeable (including being hot-swappable) on the line card of the network device.
As shown in FIG. 1, optical loopbacks can be utilized for testing. In this instance, a transmit optical fiber can be looped back to also serve as the receive optical fiber. Also, the optical signal can be attenuated (such as by a computer controlled attenuator or shutter) for testing purposes. Additionally, an optical fiber can be manually pulled. Lastly, test equipment 7 can be utilized through an optical transceiver module.
Each of the solutions shown in FIG. 1 typically requires every optical port on the line card to be filled with an optical transceiver. This can result in one of the largest expenses in releasing new optical network products as the optical transceivers are expensive.
Furthermore, many of the solutions provide further disadvantages. For example, a computer controlled attenuator can be expensive and bulky, which can be problematic since it has to be moved from port to port. Manually pulling the optical fiber is a slow process and wears out the optics. Lastly, the constant plugging and unplugging of shared optics that are moved from one port to another wears out the plugs (e.g., they may only be rated for 50 cycles).
Electrically looped back optical transceivers have been produced to attempt to address some of the shortcomings of conventional testing methods. However, the results of these solutions have not been satisfactory in many situations.
It would be beneficial to have innovative techniques for providing electrically looped back transceiver modules that provides flexibility in testing while savings costs. Additionally, it would be beneficial if the transceiver module can be instructed to emulate faults.